反应详情

A mixture of methyl 2,4-dihydroxy-5-isopropylbenzoate (420 mg, 2.0 mmol) and anhydrous potassium carbonate (662 mg, 4.8 mmol) in acetonitrile (10 ml) was treated with allyl bromide (0.364 ml, 4.2 mmol) and the mixture was stirred at room temperature for 16 hours. A further portion of allyl bromide (0.364 ml, 4.2 mmol) was added and the mixture was stirred and held at reflux for a further 16 hours. Upon cooling to room temperature the solvent was removed in vacuo and the residue acidified by the addition of 2M hydrochloric acid (20 ml). The organic material was extracted with ethyl acetate (2×20 ml) and the combined organic extracts were evaporated in vacuo to afford methyl 2,4-bis-allyloxy-5-isopropylbenzoate (480 mg, 83%) as a pale yellow oil. 1H NMR (DMSO-d6) 7.56 (1H, s), 6.68 (1H, s), 6.07 (2H, m), 5.51 (1H, dm), 5.44 (1H, dm), 5.28 (2H, m), 4.68 (2H, m), 4.64 (2H, m), 3.75 (3H, s), 3.18 (1H, m), 1.16 (6H, d). MS: [M+Na]+ 313.

1. stirringthe mixture was stirred
2. temperatureat reflux for a further 16 hours
3. temperatureUpon cooling to room temperature the solvent
4. customwas removed in vacuo
5. additionthe residue acidified by the addition of 2M hydrochloric acid (20 ml)
6. extractionThe organic material was extracted with ethyl acetate (2×20 ml)
7. customthe combined organic extracts were evaporated in vacuo